WASHINGTON – The government on Wednesday designated six leaders of the violent street gang MS-13 as international criminals, stepping up a crackdown on the sprawling U.S. and Central American gang’s finances.

The Treasury Department in October designated MS-13, or Mara Salvatrucha, as an international criminal organization. The Obama administration said that makes the gang subject to penalties by the Office of Foreign Assets Control and gives the U.S. an opportunity to hinder MS-13’s ability to funnel money to its leaders in El Salvador or launder criminal proceeds through otherwise legitimate businesses.

Adding the names of six of the gang’s purported leaders allows the U.S. to target their bank accounts individually.

All are from El Salvador. Turcios, Rivera-Luna and Monterrosa-Larios have been indicted in the United States on criminal charges. Rivera-Luna and Monterrosa-Larios are jailed in El Salvador and Turcios’ whereabouts are unknown. Federal court records do not list attorneys of any of the three men.

Henriquez is believed to be the head of the gang’s operations in El Salvador, despite being jailed in the Central American country.

The six men could not immediately be located by The Associated Press for comment.

Adam Szubin, who is the head of OFAC, said federal authorities are moving to freeze any assets the men may have in the United States, whether it be bank accounts or real property. While at least four of the six gang leaders are believed to be in prison in El Salvador, authorities believe they are still actively directing MS-13 operations and profiting from crimes including human and drug smuggling, racketeering, extortion and kidnapping.

Waldemar Rodriguez, Immigration and Customs Enforcement deputy assistant director for transnational crime and public safety, said financial penalties are part of a broader effort to halt the gang’s activities in the U.S. Since 2006, about 4,200 MS-13 members have been arrested “yet international criminal activities continue.”

“MS-13 is a rising public threat,” Rodriguez said. “We must take them on where ever they are.”

The gang was founded more than two decades ago by immigrants flee El Salvador’s civil war. Taking lessons from the brutal conflict to the streets of Los Angeles, its founders built a reputation as one of the most ruthless and sophisticated street gangs, according to U.S. Immigration and Customs Enforcement Special Agent Jason Shatarsky.

MS-13 has a strong presence in Southern California, the District of Columbia and northern Virginia, all areas with substantial Salvadoran populations, and as many 10,000 members in 46 states. The gang is also allied with several of Mexico’s warring drug cartels.

Shatarsky has said MS-13 members target residents and business owners for extortion, among other crimes. The gang is active throughout Central America and in parts of Mexico, too. Authorities in Europe have reported evidence of MS-13 expanding operations there.

Numerous killings in the U.S. have been attributed to the gang, including the 2003 slaying a pregnant Virginia teenager who had become an informant. Brenda Paz, 17, was stabbed to death and her body was left along the banks of the Shenandoah River.

Gang members have been linked to the 2007 execution style shooting deaths of three friends in a schoolyard in Newark, N.J. One victim was slashed with a machete before being shot. Six people have been charged in the case.